1. Field of the Invention
The present invention relates to a stereoscopic image displaying method and a stereoscopic display device thereof, more particularly, to a stereoscopic image displaying method for reducing the crosstalk of left eye image and right eye image and a stereoscopic display device thereof.
2. Description of the Prior Art
Stereoscopic image displaying methods may be mainly categorized into two groups: time-sequential stereoscopic image displaying method and spatial stereoscopic image displaying method. In the time-sequential stereoscopic image displaying method, projectors are widely utilized. For example, as described in U.S. Pat. No. 4,504,856, two projectors offer the stereoscopic image by alternately providing the left eye image and the right eye image. The volume of conventional projectors, however, is overlarge, which increases complexity in designing optical elements and driving circuits of the projectors, and further raises the production cost. On the other hand, the spatial stereoscopic image displaying method suffers from low resolution. For example, as described in U.S. Pat. Nos. 5,007,715 or 5,264,964, the display panel provides the left eye image and the right eye image at the same time. With the aid of a pair of polarization glasses, the left eye image is received by the left eye of the observer and the right eye image is received by the right eye of the observer. Because the display panel shows two sets of images at one time, in some cases the resolution will drop to 50%, causing the disadvantage of low-resolution.
In addition, the polarization glasses may be utilized in the time-sequential stereoscopic image displaying method which alternately provides the left eye image and the right eye image in a time sequence. Please refer to FIG. 1. FIG. 1 is a schematic diagram illustrating the operation of the stereoscopic display device in the prior art. As shown in FIG. 1, a first left eye data L1, a vertical blanking interval VBI, a first right eye data R1, a vertical blanking interval VBI, and a second left eye data L2 are sequentially provided. With the aid of the polarization glasses, the first left eye data L1 and the second left eye data L2 are received by the left eye of the observer, and the first right eye data R1 is received by the right eye of the observer. For example, when time is T2, the whole frame is the required display image (i.e. the first right eye data R1). However, the display data are displayed on the frame by scanning, such as by sequentially scanning from top to bottom in FIG. 1. Accordingly, only a portion of the whole frame may show the required display image at a certain time, and the observer can not receive the complete and correct image. For instance, when time is T1, the right eye of the observer may receive a portion of the first right eye data R1 and a portion of the first left eye data L1 at the same time; when time is T3, the left eye of the observer may receive a portion of the second left eye data L2 and a portion of the first right eye data R1 at the same time. As a result, each eye of the observer may receive both of the left eye data and the right eye data within a period of time, and the quality of the display images may be deteriorated due to the crosstalk of the left eye image and the right eye image.